Overlapping activity layouts in navigation drawer xml

Question

this is the first app I program and I have the following problem: My activity_navigation_drawer looks as follows:

<?xml version="1.0" encoding="utf-8"?>
  <android.support.v4.widget.DrawerLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start"
    app:layout_behavior="@string/appbar_scrolling_view_behavior">

  <include layout="@layout/app_bar_navigation_drawer"/>

  <include layout="@layout/content_navigation_drawer"/>

  <android.support.design.widget.NavigationView
      android:id="@+id/nav_view"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:layout_gravity="start"
      android:fitsSystemWindows="true"
      app:headerLayout="@layout/nav_header_navigation_drawer"
      app:menu="@menu/activity_navigation_drawer_drawer" />

</android.support.v4.widget.DrawerLayout>

In this xml file I included my appbar and the content I will add under this addbar. Unfortunatelly the content overlaps the entire appbar(In other words, the two layouts I did include are overlapping)

appbar.xml:

<?xml version="1.0" encoding="utf-8"?>
  <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    tools:context="...NavigationDrawerActivity">

    <android.support.design.widget.AppBarLayout
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:theme="@style/AppTheme.AppBarOverlay">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:popupTheme="@style/AppTheme.PopupOverlay" />

 </android.support.design.widget.AppBarLayout>
</RelativeLayout>

content.xml:

<?xml version="1.0" encoding="utf-8"?>
  <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  app:layout_behavior="@string/appbar_scrolling_view_behavior"
  tools:context="...NavigationDrawerActivity">

  <include layout="@layout/activity_function_overview" />
</RelativeLayout>

What am I doing wrong here?

Answer 1

In your appbar.xml , use LinearLayout as root layout with vertical orientation.

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:orientation="vertical"
      tools:context="...NavigationDrawerActivity">

      <android.support.design.widget.AppBarLayout
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:theme="@style/AppTheme.AppBarOverlay">

      <android.support.v7.widget.Toolbar
          android:id="@+id/toolbar"
          android:layout_width="match_parent"
          android:layout_height="?attr/actionBarSize"
          android:background="?attr/colorPrimary"
          app:popupTheme="@style/AppTheme.PopupOverlay" />

     </android.support.design.widget.AppBarLayout>

     <!-- Your content layout here -->

</LinearLayout>

FYI, you can also use android.support.design.widget.CoordinatorLayout for some extra features.